<?php
/*
 * Copyright (c) 2017 Baidu.com, Inc. All Rights Reserved
 *
 * Licensed under the Apache License, Version 2.0 (the "License"); you may not
 * use this file except in compliance with the License. You may obtain a copy of
 * the License at
 *
 * Http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS, WITHOUT
 * WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the
 * License for the specific language governing permissions and limitations under
 * the License.
 */

namespace addons\getwords\library\lib;

/**
 * Aip Base 基类
 */
class AipBase
{

    /**
     * 获取access token url
     * @var string
     */
    protected $accessTokenUrl = 'https://aip.baidubce.com/oauth/2.0/token';

    /**
     * 反馈接口
     * @var string
     */
    protected $reportUrl = 'https://aip.baidubce.com/rpc/2.0/feedback/v1/report';

    /**
     * appId
     * @var string
     */
    protected $appId = '';

    /**
     * apiKey
     * @var string
     */
    protected $apiKey = '';

    /**
     * secretKey
     * @var string
     */
    protected $secretKey = '';

    /**
     * 权限
     * @var array
     */
    protected $scope = 'brain_all_scope';

    /**
     * @param string $appId
     * @param string $apiKey
     * @param string $secretKey
     */
    public function __construct($appId, $apiKey, $secretKey)
    {
        $this->appId       = trim($appId);
        $this->apiKey      = trim($apiKey);
        $this->secretKey   = trim($secretKey);
        $this->isCloudUser = null;
        $this->client      = new AipHttpClient();
        $this->version     = '2_2_19';
        $this->proxies     = array();
    }

    /**
     * 查看版本
     * @return string
     *
     */
    public function getVersion()
    {
        return $this->version;
    }

    /**
     * 连接超时
     * @param int $ms 毫秒
     */
    public function setConnectionTimeoutInMillis($ms)
    {
        $this->client->setConnectionTimeoutInMillis($ms);
    }

    /**
     * 响应超时
     * @param int $ms 毫秒
     */
    public function setSocketTimeoutInMillis($ms)
    {
        $this->client->setSocketTimeoutInMillis($ms);
    }

    /**
     * 代理
     * @param array $proxy
     * @return string
     *
     */
    public function setProxies($proxies)
    {
        $this->client->setConf($proxies);
    }

    /**
     * 处理请求参数
     * @param  string $url
     * @param array $params
     * @param array $data
     * @param array $headers
     */
    protected function proccessRequest($url, &$params, &$data, $headers)
    {
        $params['aipSdk']        = 'php';
        $params['aipSdkVersion'] = $this->version;
    }

    /**
     * Api 请求
     * @param  string $url
     * @param  mixed $data
     * @return mixed
     */
    protected function request($url, $data, $headers = array())
    {
        try {
            $result = $this->validate($url, $data);
            if ($result !== true) {
                return $result;
            }

            $params  = array();
            $authObj = $this->auth();

            if ($this->isCloudUser === false) {
                $params['access_token'] = $authObj['access_token'];
            }

            // 特殊处理
            $this->proccessRequest($url, $params, $data, $headers);

            $headers  = $this->getAuthHeaders('POST', $url, $params, $headers);
            $response = $this->client->post($url, $data, $params, $headers);

            $obj = $this->proccessResult($response['content']);

            if (!$this->isCloudUser && isset($obj['error_code']) && $obj['error_code'] == 110) {
                $authObj                = $this->auth(true);
                $params['access_token'] = $authObj['access_token'];
                $response               = $this->client->post($url, $data, $params, $headers);
                $obj                    = $this->proccessResult($response['content']);
            }

            if (empty($obj) || !isset($obj['error_code'])) {
                $this->writeAuthObj($authObj);
            }
        } catch (Exception $e) {
            return array(
                'error_code' => 'SDK108',
                'error_msg'  => 'connection or read data timeout',
            );
        }

        return $obj;
    }

    /**
     * Api 多个并发请求
     * @param  string $url
     * @param  mixed $data
     * @return mixed
     */
    protected function multi_request($url, $data)
    {
        try {
            $params  = array();
            $authObj = $this->auth();
            $headers = $this->getAuthHeaders('POST', $url);

            if ($this->isCloudUser === false) {
                $params['access_token'] = $authObj['access_token'];
            }

            $responses = $this->client->multi_post($url, $data, $params, $headers);

            $is_success = false;
            foreach ($responses as $response) {
                $obj = $this->proccessResult($response['content']);

                if (empty($obj) || !isset($obj['error_code'])) {
                    $is_success = true;
                }

                if (!$this->isCloudUser && isset($obj['error_code']) && $obj['error_code'] == 110) {
                    $authObj                = $this->auth(true);
                    $params['access_token'] = $authObj['access_token'];
                    $responses              = $this->client->post($url, $data, $params, $headers);
                    break;
                }
            }

            if ($is_success) {
                $this->writeAuthObj($authObj);
            }

            $objs = array();
            foreach ($responses as $response) {
                $objs[] = $this->proccessResult($response['content']);
            }

        } catch (Exception $e) {
            return array(
                'error_code' => 'SDK108',
                'error_msg'  => 'connection or read data timeout',
            );
        }

        return $objs;
    }

    /**
     * 格式检查
     * @param  string $url
     * @param  array $data
     * @return mix
     */
    protected function validate($url, &$data)
    {
        return true;
    }

    /**
     * 格式化结果
     * @param $content string
     * @return mixed
     */
    protected function proccessResult($content)
    {
        return json_decode($content, true);
    }

    /**
     * 返回 access token 路径
     * @return string
     */
    private function getAuthFilePath()
    {
        return dirname(__FILE__) . DIRECTORY_SEPARATOR . md5($this->apiKey);
    }

    /**
     * 写入本地文件
     * @param  array $obj
     * @return void
     */
    private function writeAuthObj($obj)
    {
        if ($obj === null || (isset($obj['is_read']) && $obj['is_read'] === true)) {
            return;
        }

        $obj['time']          = time();
        $obj['is_cloud_user'] = $this->isCloudUser;
        @file_put_contents($this->getAuthFilePath(), json_encode($obj));
    }

    /**
     * 读取本地缓存
     * @return array
     */
    private function readAuthObj()
    {
        $content = @file_get_contents($this->getAuthFilePath());
        if ($content !== false) {
            $obj               = json_decode($content, true);
            $this->isCloudUser = $obj['is_cloud_user'];
            $obj['is_read']    = true;
            if ($this->isCloudUser || $obj['time'] + $obj['expires_in'] - 30 > time()) {
                return $obj;
            }
        }

        return null;
    }

    /**
     * 认证
     * @param bool $refresh 是否刷新
     * @return array
     */
    private function auth($refresh = false)
    {

        //非过期刷新
        if (!$refresh) {
            $obj = $this->readAuthObj();
            if (!empty($obj)) {
                return $obj;
            }
        }

        $response = $this->client->get($this->accessTokenUrl, array(
            'grant_type'    => 'client_credentials',
            'client_id'     => $this->apiKey,
            'client_secret' => $this->secretKey,
        ));

        $obj = json_decode($response['content'], true);

        $this->isCloudUser = !$this->isPermission($obj);
        return $obj;
    }

    /**
     * 判断认证是否有权限
     * @param  array   $authObj
     * @return boolean
     */
    protected function isPermission($authObj)
    {
        if (empty($authObj) || !isset($authObj['scope'])) {
            return false;
        }

        $scopes = explode(' ', $authObj['scope']);

        return in_array($this->scope, $scopes);
    }

    /**
     * @param  string $method HTTP method
     * @param  string $url
     * @param  array $param 参数
     * @return array
     */
    private function getAuthHeaders($method, $url, $params = array(), $headers = array())
    {

        //不是云的老用户则不用在header中签名 认证
        if ($this->isCloudUser === false) {
            return $headers;
        }

        $obj = parse_url($url);
        if (!empty($obj['query'])) {
            foreach (explode('&', $obj['query']) as $kv) {
                if (!empty($kv)) {
                    list($k, $v) = explode('=', $kv, 2);
                    $params[$k]  = $v;
                }
            }
        }

        //UTC 时间戳
        $timestamp             = gmdate('Y-m-d\TH:i:s\Z');
        $headers['Host']       = isset($obj['port']) ? sprintf('%s:%s', $obj['host'], $obj['port']) : $obj['host'];
        $headers['x-bce-date'] = $timestamp;

        //签名
        $headers['authorization'] = AipSampleSigner::sign(array(
            'ak' => $this->apiKey,
            'sk' => $this->secretKey,
        ), $method, $obj['path'], $headers, $params, array(
            'timestamp'     => $timestamp,
            'headersToSign' => array_keys($headers),
        ));

        return $headers;
    }

    /**
     * 反馈
     *
     * @param array $feedbacks
     * @return array
     */
    public function report($feedback)
    {

        $data = array();

        $data['feedback'] = $feedback;

        return $this->request($this->reportUrl, $data);
    }

    /**
     * 通用接口
     * @param string $url
     * @param array $data
     * @param array header
     * @return array
     */
    public function post($url, $data, $headers = array())
    {
        return $this->request($url, $data, $headers);
    }

}
